The present invention relates to an apparatus for the compacting of articles e.g., disposable plastic bottles, consisting of a pair of mutually counter-rotatable interacting squeeze rollers, wherein the first roller has a fixed support and wherein the second roller is supported in an arm-spring assembly, thereby enabling the space between the rollers to be varied according to the size and compactability of the article, and wherein the apparatus in addition is provided with a precompactor consisting of a conveyor, e.g., a belt or chain conveyor, and an elongate squeeze device inclined relative to the conveyor and preferably spring-loaded, to ensure that the article is gradually flattened upstream of the squeeze rollers.
An apparatus of this kind is known, for example, from Finnish Patent 93175.
However, a compactor of the said type has the drawback that the compaction becomes sufficient. When using a compactor apparatus of this kind in connection with a reverse vending machine for cans and/or bottles, it is essential that the articles are flattened and remain permanently flat, as this is necessary in order to be able to transport a large number of returned goods of this kind in an inexpensive manner. When compacting, e.g., plastic bottles, the bottle neck and any screw cap attached thereto, and the concave bottom nipple of the bottle will, often cause compaction problems.
The object of the invention is therefore to provide a special squeeze roller device, and a precompactor for articles, e.g., disposable metal cans or disposable plastic bottles which are to be compacted, and wherein the precompactor feeds the articles to a subsequent final compactor.
The object of the present invention is therefore to overcome the drawbacks associated with the prior art and to provide a solution which provides a best possible compaction.
According to the invention, the aforementioned apparatus is characterised in that the rollers have an incurvate middle portion so as to provide a virtually clear passageway for the mouth and bottom nipple of the article. This allows a best possible total compaction of the article to be obtained.
In an alternative embodiment, the apparatus is characterised in that there is cut out in the surface of the rollers at least one opening or recess having an L, U or V-shaped cross-section and having a gripping edge, so that the gripping edges on opposing rollers directly interact, and upon their rotation as a pair will abut, the interacting gripping edges having the same radial distance from the rotation axis of the respective roller, and in that on such interaction the depressions in the rollers form a space therebetween. This is of importance if the article, e.g., enters askew as it moves towards the squeeze rollers or has elements which otherwise will not easily pass the rollers.
Additional embodiments of the apparatus will be apparent from the following description with reference to the attached drawings, and from the attached patent claims.